Analogues of cyclophosphamide substituted with various groups on the ring carbons and the exocyclic nitrogen are being synthesized for stereochemical study and biological evaluation as carcinostats. Complexes of the trivalent phosphorus forms of these compunds will also be synthesized and studied for these purposes. Efficient synthetic routes to neutral ester analogues of cyclic 3', 5' adenosine monophosphate are being sought in an effort to investigate the stereochemical preference of phosphorus in this biologically important system and the charge distribution on the exocyclic oxygens in the parent compound.